Kwangwoo Nam1, Dong Uk Kim2, Tae Hoon Lee3, Takuji Iwashita4, Yousuke Nakai5, Ahmed Bolkhir6, Lara Aguilera Castro7, Enrique Vazquez-Sequeiros7, Carlos de la Serna8, Manuel Perez-Miranda8, John G Lee9, Sang Soo Lee10, Dong-Wan Seo10, Sung Koo Lee10, Myung-Hwan Kim10, Do Hyun Park10. 1. Department of Internal Medicine, Dankook University College of Medicine, Cheonan, South Korea. 2. Division of Gastroenterology, Department of Internal Medicine, Biomedical Institute, Pusan National University Hospital, Pusan National University School of Medicine, Busan, South Korea. 3. Department of Internal Medicine, Soonchunhyang University School of Medicine, Cheonan, South Korea. 4. First Department of Internal Medicine, Gifu University Hospital, Gifu, Japan. 5. Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 6. Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA. 7. Department of Gastroenterology and Hepatology, IRYCIS, University Hospital Ramon y Cajal, Móstoles, Madrid, Spain. 8. Department of Gastroenterology and Hepatology, Rio Hortega University Hospital, Valladolid, Spain. 9. Division of Gastroenterology and Hepatology, The University of California Irvine Health, Orange, CA, USA. 10. Department of Internal Medicine, Division of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Abstract
BACKGROUND AND OBJECTIVES: EUS-guided biliary drainage (EUS-BD) is a feasible procedure when ERCP fails, as is percutaneous transhepatic BD (PTBD). However, little is known about patient perception and preference of EUS-BD and PTBD. PATIENTS AND METHODS: An international multicenter survey was conducted in seven tertiary referral centers. In total, 327 patients, scheduled to undergo ERCP for suspected malignant biliary obstruction, were enrolled in the study. Patients received decision aids with visual representation regarding the techniques, benefits, and adverse events (AEs) of EUS-BD and PTBD. Patients were then asked the choice between the two simulated scenarios (EUS-BD or PTBD) after failed ERCP, the reasons for their preference, and whether altering AE rates would influence their prior choice. RESULTS: In total, 313 patients (95.7%) responded to the questionnaire and 251 patients (80.2%) preferred EUS-BD. The preference of EUS-BD was 85.7% (186/217) with EUS-BD expertise, compared to 67.7% (65/96) without EUS-BD expertise (P < 0.001). The main reason for choosing EUS-BD was the possibility of internal drainage (78.1%). In multivariate analysis, the availability of EUS-BD expertise was the single independent factor that influenced patient preference (odds ratio: 3.168; 95% of confidence interval, 1.714-5.856; P < 0.001). The preference of EUS-BD increased as AE rates decreased (P < 0.001). CONCLUSIONS: In this simulated scenario, approximately 80% of patients preferred EUS-BD over PTBD after failed ERCP. However, preference of EUS-BD declined as its AE rates increased. Further technical innovations and improved proficiency in EUS-BD for reducing AEs may encourage the use of this procedure as a routine clinical practice when ERCP fails.
BACKGROUND AND OBJECTIVES: EUS-guided biliary drainage (EUS-BD) is a feasible procedure when ERCP fails, as is percutaneous transhepatic BD (PTBD). However, little is known about patient perception and preference of EUS-BD and PTBD. PATIENTS AND METHODS: An international multicenter survey was conducted in seven tertiary referral centers. In total, 327 patients, scheduled to undergo ERCP for suspected malignant biliary obstruction, were enrolled in the study. Patients received decision aids with visual representation regarding the techniques, benefits, and adverse events (AEs) of EUS-BD and PTBD. Patients were then asked the choice between the two simulated scenarios (EUS-BD or PTBD) after failed ERCP, the reasons for their preference, and whether altering AE rates would influence their prior choice. RESULTS: In total, 313 patients (95.7%) responded to the questionnaire and 251 patients (80.2%) preferred EUS-BD. The preference of EUS-BD was 85.7% (186/217) with EUS-BD expertise, compared to 67.7% (65/96) without EUS-BD expertise (P < 0.001). The main reason for choosing EUS-BD was the possibility of internal drainage (78.1%). In multivariate analysis, the availability of EUS-BD expertise was the single independent factor that influenced patient preference (odds ratio: 3.168; 95% of confidence interval, 1.714-5.856; P < 0.001). The preference of EUS-BD increased as AE rates decreased (P < 0.001). CONCLUSIONS: In this simulated scenario, approximately 80% of patients preferred EUS-BD over PTBD after failed ERCP. However, preference of EUS-BD declined as its AE rates increased. Further technical innovations and improved proficiency in EUS-BD for reducing AEs may encourage the use of this procedure as a routine clinical practice when ERCP fails.
Entities:
Keywords:
Drainage; endosonography; patient preference; surveys and questionnaires
ERCP with biliary drainage (BD) is a standard procedure for malignant biliary obstruction.[12] However, ERCP may fail in certain patients due to failed transpapillary cannulation or an inaccessible papilla caused by the duodenal invasion of the malignant tumor.[34567] The failure rate of ERCP is reported to be up to 7%,[8] and percutaneous transhepatic BD (PTBD) is a conventional option in such cases. PTBD has been demonstrated to have a high success rate (87%–100%).[9] However, the requisite external catheter placement is a major drawback, in addition to several adverse events (AEs) including pneumothorax, hepatic arterial injury, bile duct injury, and liver abscess.[101112] As a result, many endoscopists sought to identify a less invasive procedure than PTBD.Since the first report by Giovannini et al. in 2001,[13] EUS-guided BD (EUS-BD) has been reported to be a feasible and effective BD procedure when ERCP fails. EUS-BD has been demonstrated to have a technical success rate of approximately 90% and an AE rate of 17%.[91415161718] It has specific advantages over PTBD, as follows: (1) it can be performed in a single session when ERCP has been unsuccessful, (2) it can provide immediate internal drainage with less physical discomfort,[19] and (3) it is potentially cost-effective, with fewer unscheduled reintervention over long-term follow-up.[1920] However, EUS-BD requires experienced endoscopists with advanced endoscopic capabilities and appropriate radiological/surgical backup to manage failed interventions and/or AEs.Although endoscopists with EUS-BD expertise may prefer EUS-BD over PTBD after failed ERCP due to the potential benefits of EUS-BD including a possible one-stage procedure in the same ERCP unit and internal drainage, patient perception and preference of EUS-BD are not well understood. Since patients’ medical knowledge was limited and personal patient preference had not been incorporated in medical decision-making, it was difficult to make patient-centered decision in real clinical practice. Recently, shared decision-making model between patient and physician has been suggested,[2122] and patient decision aids which help appropriate informed choice has been evaluated.[23] Eliciting the personal preference of the patient then working to align these values and preference with shared decision-making strengthens the therapeutic alliance and is more protective of the provider in a medico-legal context.[24] Poor communication by the provider and inadequate knowledge on the part of the patient are often precursors for medical liability claim.[25]The primary aim of this study was to determine whether patients with suspected malignant biliary obstruction enrolled prefer EUS-BD or PTBD under a simulated scenario (after failed ERCP) with decision aids. The secondary aim was to assess whether altering AEs rates in EUS-BD influenced the patient selection of EUS-BD and/or PTBD.
PATIENTS AND METHODS
Study population
This study was an international multicenter cross-sectional survey of patients scheduled to undergo ERCP for suspected malignant obstruction. Participation in the study was voluntary, and compensation was not provided. An informational booklet describing EUS-BD and PTBD as rescue procedures when ERCP fails, which contained details of the techniques, benefits, and AEs relating to each procedure was provided to the study participants. Once the informational booklet was read, the survey was administered to consecutive patients.Seven tertiary referral centers in South Korea, Japan, and Spain were participated in this study. Of these, EUS-BD was available in five centers, and PTBD was available at all of them. Participants who preferred EUS-BD were informed as to whether EUS-BD could be performed at their center. Along with the survey, informed consent to undergo any of the available BD procedures (ERCP, EUS-BD, and PTBD) was obtained from the patients before ERCP. The institutional review board for each institution approved the study protocol.
Informational booklet and survey
A third party in the United States created the informational booklet [Supplementary Appendix 1] with visual aids and questionnaire [Supplementary Appendix 2] to minimize selection bias with respect to the endoscopists. The survey was simplified using a subject choice followed by an explanation choice model, and it was written in easily understandable 5th grade US English for patients without medical knowledge. In an attempt to create a reliable and valid questionnaire, the survey was first administered to 34 3rd-year medical students at the University of Ulsan College of Medicine, Seoul, South Korea, and pilot-tested for clarity and internal consistency [Supplementary Appendix 3]. As a result, the questionnaire demonstrated high internal consistency, with a Cronbach's α value of 0.82. The forms then were translated into Korean, Japanese, and Spanish.Click here for additional data file.Click here for additional data file.Click here for additional data file.The survey was administered to the participants by trained research assistants who read from a standardized script. The patients were allowed sufficient time to read the information booklet and complete the questionnaire. A detailed explanation or discussion of each procedure was not permitted to minimize the risk of selection bias. It was clearly stated that the patient's preference would not be disclosed to the attending physician and it would not affect the treatment plan. The results were blinded to ensure patient anonymity.The questionnaire started with questions on age, sex, ethnicity, and prior endoscopy, ERCP, and PTBD [Supplementary Appendix 2]. First, participants were questioned as to their preference of a rescue procedure (EUS-BD or PTBD) to be performed in the event of failed ERCP and were asked to provide the reasons for their preference. Choice options listed for EUS-BD were as follows: (1) It can be done at the same time during the ERCP, so you do not have to come back again for another procedure, (2) It has a higher success rate and relatively low AEs, and (3) It is comfortable, so you do not have drain tube through the skin (such as PTBD). Choice options listed for a PTBD were as follows: (1) It takes less time to place it (quicker), (2) It is cheaper, (3) It is safer (lower AEs), and (4) It is more convenient (easy to perform for the operator). Patients were also permitted to write down any unlisted reasons for their preference.Patients were then asked whether their opinion would change depending on altering AE rates of EUS-BD compared to those of PTBD (9%–33%). To reduce the chance of selection bias among EUS-BD experts, two centers without EUS-BD experts (two South Korean centers), three centers with EUS-BD experts (one South Korea center and two Spanish centers), and two centers with experts in both EUS-BD and PTBD (two Japanese centers) were invited to participate.
Statistical analyses
The participants were divided into two groups according to the procedure of their choosing (EUS-BD vs. PTBD). Statistical analysis was performed using SPSS software version 21.0 (SPSS Inc., Chicago, IL). Continuous variables were reported as the mean and standard deviation and were compared between the groups using the unpaired t-test. Categorical variables were reported as frequencies and percentages and were evaluated using Fisher's exact test. The value of P < 0.05 was considered to be statistically significant.To calculate the sample size, it was assumed that two-thirds (66%) of the sample would prefer EUS-BD. A sample size of 75 was identified to determine whether this proportion was significantly different from 50% a priori, with an alpha of 0.05 and a power of 80%. Assuming a 30% response rate, we planned to recruit 350 patients (50 patients from each institution).
RESULTS
In total, 327 patients who were scheduled to undergo ERCP due to suspected malignant biliary obstruction were recruited and of these, 313 patients completed the questionnaire (response rate: 95.7%) [Figure 1]. The demographic characteristics of the study participants are shown in Table 1. The mean age was 64 years (range: 34–88 years), and 182 of the respondents (58.1%) were male. The suspected diagnoses of the respondents based on imaging studies (abdominopelvic computed tomography and/or magnetic resonance cholangiopancreatography) were cholangiocarcinoma in 101 (32.3%), gallbladder cancer in 25 (8%), ampullary cancer in 20 (6.4%), pancreatic head cancer in 93 (29.7%), hepatocellular carcinoma in seven (2.2%), metastatic lymph node in five (1.6%), and indeterminate biliary stricture in 62 (19.8%).
Figure 1
Flow diagram for study
Table 1
Baseline characteristics of patients and factors influencing the preference for EUS-BD in univariate analysis
Flow diagram for studyBaseline characteristics of patients and factors influencing the preference for EUS-BD in univariate analysisAmong these, 258 patients (82.4%) had previously undergone endoscopy, 163 patients (52.1%) had undergone ERCP, and 55 patients (17.6%) had undergone PTBD. There were no differences in preference between EUS-BD and PTBD within three subgroups. EUS-BD was preferred by 186 of 217 participants (85.7%) at the five centers which EUS-BD was available, compared to 65 of 96 patients (67.7%) at the two centers which it was unavailable (P < 0.001). There was no significant difference in preference of EUS-BD according to the region (Asia vs. Europe) or race (Asian vs. non-Asian) [Table 1].In multivariate analysis, the availability of EUS-BD expertise was the single independent factor that influenced patient preference (odds ratio [OR] 3.168; 95% of confidence interval [CI] 1.714–5.856; P < 0.001) [Table 2]. Reasons for selecting EUS-BD included less physical discomfort without percutaneous drain tube placement (196/251, 78.1%), a higher success rate with relatively lower morbidity (110/251, 43.8%), and the ability to be performed at the same time as the ERCP (71/251, 28.3%). By contrast, reasons for selecting PTBD included proven technical safety (43/62, 69.4%), shorter procedure time (18/62, 29%), technical easiness (8/62, 12.9%), and cost-effectiveness (4/62, 6.5%) [Figure 2].
Table 2
Factors influencing the preference for EUS-guided biliary drainage in multivariate logistic regression analysis
Figure 2
Graph demonstrating the reasons behind patient preference
Factors influencing the preference for EUS-guided biliary drainage in multivariate logistic regression analysisGraph demonstrating the reasons behind patient preferenceFor the second question, preference of EUS-BD decreased as AE rates increased (P < 0.001). Two-hundred and one of 217 participants (92.6%) at the five centers with EUS-BD expertise were willing to undergo PTBD if AE rates of EUS-BD were higher than those of PTBD (range: 9%–33%). In contrast, if AE rates of EUS-BD were lower when compared to those of PTBD, 93 of 96 participants (96.9%) at the two centers without EUS-BD expertise were willing to undergo EUS-BD. There was no significant difference in patient preference based on AE rates of EUS-BD according to the availability of EUS-BD expertise [Figure 3a] or the region (Asia vs. Europe) [Figure 3b].
Figure 3
Relationship between patient preference and adverse event rates for EUS-guided biliary drainage depending on (a) the availability of EUS-guided biliary drainage expertise and (b) the region
Relationship between patient preference and adverse event rates for EUS-guided biliary drainage depending on (a) the availability of EUS-guided biliary drainage expertise and (b) the region
DISCUSSION
To the best of our knowledge, this is the first study to focus on the patient preference of BD procedures in patients with suspected malignant biliary obstruction. In this survey, most patients would prefer EUS-BD to PTBD when ERCP fails due to the ability to undergo internal drainage without the need for a percutaneous drain tube. Preference of EUS-BD was significantly higher at centers with EUS-BD expertise compared to centers without EUS-BD expertise (85.7% vs. 67.7%, respectively; P < 0.001). In multivariate analysis, the availability of EUS-BD expertise was significantly associated with the preference of EUS-BD (OR 3.168, 95% CI 1.714–5.856, P < 0.001). In addition, patient willingness to undergo EUS-BD was observed to decline in the context of higher AE rates compared to PTBD.EUS-BD has been reported to be a feasible BD technique. In a recent randomized controlled trial, EUS-BD was compared with PTBD after failed ERCP in patients with malignant biliary obstruction.[26] In that study, EUS-BD showed technical success rates comparable to those of PTBD (94.1% vs. 96.9%, respectively), and fewer AE rates compared to PTBD (8.8% vs. 31.2%, respectively). Although detailed data on EUS-BD are limited, there are clear advantages to EUS-BD, including the possibility of internal drainage without the placement of a percutaneous drain tube, and the fact that EUS-BD can be performed in the same session after failed ERCP provided appropriate informed consent is obtained.In this study, before ERCP, patients were asked about preferred BD procedure when ERCP fails. This process may simulate obtained informed consent for possible EUS-BD before ERCP. Since the prediction of endoscopically inaccessible papilla before ERCP is difficult, unplanned PTBD after failed outpatient ERCP may occur, and it can incur additional hospitalization and an unexpected economic burden on patients and their families. Thus, we adopted an algorithm described in our previous studies,[161826] and routinely obtained informed consent for EUS-BD before ERCP, especially in patients at potential risk of unsuccessful cannulation. This approach allows the endoscopists to perform timely, one-stage BD, even in the event of the unexpected inaccessible papilla, without the difficulty of obtaining informed consent from the sedated patient in the same ERCP unit.Due to comparable safety and cost-effectiveness between the inpatient and outpatient procedures, many endoscopists perform ERCP on an outpatient basis in the United States.[27] However, unplanned admission after outpatient ERCP was reported in 10.7%–25.1% of the cases.[2829] EUS-BD has been reported to result in less physical discomfort[19] and fewer frequent unscheduled reintervention with prolonged hospital stays, which are associated with economic burden, than PTBD.[26] Thus, EUS-BD after failed ERCP in same endoscopic session may reduce the unplanned admission in the outpatient setting of ERCP. Therefore, treating patients with a preference of EUS-BD prior to ERCP may be more appealing to endoscopists with EUS-BD expertise in the United States who are able to perform outpatient ERCP compared with inpatient setting of ERCP in other country with time availability of scheduled alternative BD procedure on a different session in same day or next day after failed ERCP.In the present study, age, sex, and prior experience of endoscopy, ERCP, and PTBD were not significantly associated with a preference of EUS-BD. However, the preference of EUS-BD was lower at centers without EUS-BD expertise compared to centers with available EUS-BD expert [Figure 3a]. We believe that patients at centers without EUS-BD expertise preferred PTBD over EUS-BD because it was perceived to be a safe and readily accessible procedure without an endoscopist with EUS-BD expertise or appropriate radiological/surgical backup. Similarly, patients at centers with EUS-BD expertise preferred EUS-BD over PTBD because it was perceived to be a comfortable and readily accessible endoscopic procedure. Given the close relationship between preference of EUS-BD and its availability at their particular center, we believe that technical advancements and access to EUS-BD experts would improve patient preference and perception of EUS-BD when ERCP fails.Patient willingness to undergo EUS-BD was shown to increase when AE rates for EUS-BD were less compared to those of PTBD (9%–33%). This suggests that patients may have a fundamentally favorable perception of EUS-BD, regardless of its availability within a given center or their preference of PTBD. In a previous study, patient perception of natural orifice transluminal endoscopic surgery (NOTES), a newly developed endoscopic technique similar to EUS-BD, were evaluated,[30] and the preference of NOTES was observed to decrease with increased procedural AEs when compared to a more proven procedure (laparoscopic cholecystectomy). Similarly, in our study, the preference of EUS-BD decreased in accordance with an increase in AE rates of EUS-BD compared to those of PTBD. In these circumstances, the patient preference may be affected by the perception of PTBD with proven technical safety and easiness.We included both Asian and European patients to minimize selection bias with respect to a specific region. In the context of a decrease in AE rates of EUS-BD compared to those of PTBD (<9%), the preferential tendency of EUS-BD in Spanish patients was higher than that in Asian patients without statistical significance. However, with similar or increased AE rates of EUS-BD compared with those of PTBD, the preferential tendency for EUS-BD in Spanish patients was lower than that in Asian patients [Figure 3b]. Differences in the culture and health-care systems between Asia and Europe might have influenced patient preferential tendency of EUS-BD and PTBD according to the degree of AE rates in EUS-BD. Further investigation is necessary to understand these differences.The response rate to the questionnaire was very high (95.7%). All of the participants were scheduled to undergo ERCP for suspected malignant biliary obstruction. These patients showed interest in the detailed process of the ERCP that they would be undergoing and were concerned about the need for any subsequent procedures in the event of failed ERCP. In general, patients with suspected malignancy wanted to understand their disease and its treatment options. In a previous report, the majority of patients who underwent an EUS-FNA for suspected pancreatic cancer wished to receive the preliminary results on the day of the procedure (96.6%).[31] Similarly, we found that the participating patients in this study wished to obtain more information on the proposed procedures.The role of the patients are increasing in medical decision-making, and incorporation of patient preference into treatment is recommended in the context of shared decision-making.[23] It is reported that shared decision-making process may improve treatment outcome, patient adherence, quality of care, and reduce costs.[2122] Although the relationship between patient preference and choice of treatment options was not evaluated in this study, our informational booklet may be useful as a patient decision aid to the patients with malignant biliary obstruction when ERCP fails. Further studies about the shared decision-making process are required to evaluate patient preference and treatment outcome.There were limitations to this study. First, although we tried to provide the best available information on EUS-BD, our data were limited in terms of the safety profile and efficacy of EUS-BD, which impaired the patients’ ability to make an informed choice. For this reason, we evaluated patient preference according to whether AE rates were higher or lower than PTBD (9%–33%). Second, we did not specifically query patients regarding the type of prior endoscopy (gastroscopy vs. colonoscopy), ERCP (diagnostic vs. therapeutic), and PTBD (single vs. multiple) that they had previously undergone. This may have influenced patient perception of EUS-BD, as their preference could have been based on their previous procedural experience. Third, we did not confirm whether the patients sufficiently grasped the concept of EUS-BD. Although the informational booklet and questionnaire were written in an easily understandable language, patients with older age and a lower educational level might not have understood the questions. Finally, although the questionnaire was tested for internal consistency before its administration, it was not fully independently validated because this was a pilot study on patient preference. Medical students may not have been an accurate representation of the general patient population that was scheduled to undergo BD for malignant biliary obstruction.
CONCLUSIONS
In this international multicenter survey, approximately 80% of the patients preferred EUS-BD to PTBD after being informed of the benefits and risks of both procedures. However, preference of EUS-BD declined as its AE rates increased. Although our survey data are preliminary, patients had favorable perception of EUS-BD due to the possibility of internal drainage without a percutaneous drain tube. Further technical innovations and improved proficiency in EUS-BD for reducing AEs may increase patient preference of EUS-BD and encourage the use of this procedure as a routine clinical practice when ERCP fails.
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